Pump Up The Volume With USB
The USB link enables the connection of not just on PC gear, but also various types of home-entertainment equipment. These include audio-video receivers, DVD players--including high-definition versions such as Blu-ray and HD-DVD--and even cable and satellite set-top boxes.
Making sense of this sizable collection of gear becomes easier if you approach the USB connection in either of two ways:
- USB as the pathway to audio coming out of a PC. This can involve various kinds of signal processing or delivery, typically in the form of inline sound cards and signal processing.
- USB as a mechanism for attaching audio devices into entertainment systems. As a way to add more inputs alongside existing audio and video capabilities.
In this recipe, I will survey both these areas. I will emphasize the ways system builders can use this information to serve their customers and expand their business.
USB AS THE PATHWAY FOR AUDIO
USB turns out to be a surprisingly good method for enabling PC audio. Even the relatively old USB 1.1 standard, which tops out at 12 megabits per second (Mbps), is good enough to handle conventional stereo audio and some compressed forms of multi-channel surround sound. (Note: Don't confuse Mbps with MBps; the latter stands for mega bytes per second.)
USB 2.0, of course, is even faster--and more powerful. With a raw data rate of 480 Mbps, it is 40 times faster than USB 1.1. That means USB 2.0 offers more than enough speed to accommodate high-definition video and various 5.1 or 7.1 multi-channel surround-sound schemes.
Today's high-definition DVD formats, including HD-DVD and Blu-ray, place the biggest demands on data-transfer rates. HD-DVD rates top out at 36.55 Mbps, with 29.4 Mbps allocated for video and the rest for audio. Blu-ray tops out at 54.0 Mbps, with 40.0 Mbps for video, the rest for audio.
USB SOUND CARD ADD-ONS OR REPLACEMENTS
Several sound technologies will work with USB on PCs. These include inline sound-card replacements, USB-attached external sound-processing devices, USB audio amplifiers, controllers, and speaker systems.
For these types of products, you simply insert a new or additional sound card into the PC via a USB port. Here, you will find two types of products: USB inline sound cards, and external sound-card devices.
The distinction comes primarily in terms of size and price. The inline devices are about the same size as a USB Flash drive; the external sound card devices are usually at least as big as a pack of cards, and sometimes as big as a hardback book. Looking at price, the inline devices typically cost $20 to $40 each, while external devices run from $50 all the way to $250.
At the low end of this spectrum, USB inline devices can plug into a USB port on one end, then offer various types of audio outputs on the other end. Depending on the system, these outputs may be optical or coaxial digital audio connectors, stereo mini-jacks, standard sound card outputs, and even 5.1 analog audio outputs.
For example, Turtle Beach retails for $40 and includes an equalizer, software digital outputs for home-theater connections, and a mini-headphone jack. Sans audio or headphone cables, the unit looks pretty much like a USB Flash drive:
To view other examples of low-end devices, browse USBgear.com.
At the high end of the inline sound spectrum are numerous external sound-processing devices that attach to a PC through USB. These support a complete range of audio outputs, including digital optical and coaxial outputs, and multi-channel analog outputs (5.1 is common, but some units even offer 7.1 support). They can also support headphone outputs, microphone inputs, and analog stereo outputs.
Probably the best-known vendors in this category is Creative Labs. The company offers the Sound Blaster Live! 24-bit External device. It also offers the Audigy2 NX.
Another supplier, Hercules, offers the href="http://www.hercules.com/showpage.php?swcty=UK\&p=84\&b=1\&f=1">Muse Pocket. Here's a look at the Hercules external sound card; note the audio connections all around, and the huge volume control on top:
For system builders, upgrades to existing systems—or extensions to notebook systems—will most likely provide the best opportunities to sell such gear. Also, fully understanding how to use sound-equalization and sound-capture utilities can create new business opportunities. For example, the Sound Blaster Live! 24 can capture audio from both tape cassettes and vinyl records, then digitize this content into MP3 format. For aging baby boomers with their aging music collections, that could be one attractive service. USB AUDIO AMPLIFIERS AND CONTROLLERS
One offshoot of the PC-entertainment convergence can be described as doing away with standard AV and going all PC. Basically, this approach unites the sound-card technology with a signal processor and sound-management software. It also adds a multichannel amplifier for use with conventional audio speakers (5.1 and 7.1 rigs are currently available), or a headphone amplifier for use with a set of high-end, surround-sound-capable headphones.
Another variation on this theme is a device called a USB audio converter. It plugs in to a PC via USB to deliver optical and coaxial digital audio connections, as well as RCA analog outputs that can plug into an audio amplifier for playback.
The first variation supports using a PC as a standalone entertainment center. It does so by providing the link between a media PC, which can manage, record, and play back TV, DVDs, home videos, and digital photos. TV options include SDTV and HDTV for properly-equipped units, along with IPTV (Internet Protocol Television) for units with broadband Internet access. DVD options include high-definition formats for PCs that include Blu-ray, HD-DVD or combo-playback drives.
Next, add a set of multi-channel loudspeakers. These should include a subwoofer for low bass sounds. Plus, anywhere from two to seven front speakers.
Simplifi Digital, a leading vendor of USB-attached audio amplifiers, offers a 5.1 model designed specifically to work with Windows XP Professional Media Center Edition. The company also offers a 7.1 model that works only with optical outputs from Intel Extreme and Media Series motherboards. On a properly-equipped Media Center PC, all you need to do is plug the amplifier into an unused USB port, then hook up the speakers to the outputs on the device. The result: a complete 50-watt-per-channel 5.1 surround-sound environment.
For example, Simplifi Digital's 5075 5.1 channel USB input amp (available in black or silver) looks like a standard multi-channel audio amplifier. But the unit also includes audio control and management software that integrates with WinXP Pro Media Center Edition. Here's a look:
This same kind of equipment is much more broadly available for those seeking to unite a PC with a high-end set of headphones. Vendors including Logitech, Griffin Technology, and HeadRoom offer USB plug-ins designed to produce multi-channel sound specifically for headphones. These plug-ins are designed to deliver multi-channel (usually 5.1) sound output. This technology is especially popular with gamers and other night birds, whose fully-amplified sound might otherwise bother family, roommates, or neighbors.
Another option are devices that provide an interface between a PC and various types of outputs. For example, Trends Audio's UD-10 USB Audio Converter can link a PC with coaxial, optical and a European standard AES/EBU jack (known in the U.S. as S/PDIF). This permits a PC to essentially impersonate a high-end digital-playback device, such as a high-end music DVD or CD player. The PC can also pass digitally encoded signals into a receiver or signal pre-processor/pre-amplifier for high-end audiophile applications. Here's a look at both the front and back of the Trends Audio UD-10 device:
These devices best suit users who either already have conventional loudspeakers they'd like to use with a media PC rig, or want to bridge the gap between a media PC and an audiophile-grade home entertainment or sound system. For system builders, the biggest opportunities will come from helping clients set up PC-based entertainment systems and incorporate such systems into existing entertainment systems. USB SPEAKER SYSTEMS AND AUDIO CONTROLLERS
USB speaker systems provide another terrific alternative for those seeking to add multi-channel sound playback to a Media Center PC. Plenty of low-end offerings aim to deliver substantial sound from notebook PCs. But what really applies are multichannel playback rigs designed to either mimic 5-channel sound or deliver it outright. An example of the former is the Bose Companion 5. An example of the latter is the Altec Lansing FX5051 Powered Audio System.
The Bose Companion 5 delivers three speakers, including two satellites and a subwoofer. Technically, this qualifies the set-up as a 2.1 speaker rig: left and right front, plus subwoofer. But the Bose engineers have worked their sound and spatial magic with this relatively expensive ($400) speaker set-up. It only requires plugging the USB connector into a PC to accomplish the sound connection.
The patented Bose TrueSpace technology does a remarkable job of delivering 5.1 sound quality from a 2.1 rig. The compact format and easy cabling are offered as advantages of this approach. I tried it out, and found it to be extremely easy to hook up and position. The speakers deliver a surprising amount of acoustic output, and they would work well in an office or a small listening/viewing room. Here's a look at the Bose Companion 5 components:
Another supplier, Altec Lansing, takes a more conventional approach in its FX5051 USB-attached 5.1 speaker rig. It includes four satellites, a center speaker, and a subwoofer—all to create a real 5.1 configuration. The USB cable extends between the subwoofer and the PC, with ordinary speaker cables between the other speakers and the subwoofer to ferry signals out to all speakers.
Altec Lansing even includes a remote control. And the subwoofer has a built-in multi-channel amplifier that drives all the other speakers, as well. At a suggested retail price of just under $250, this set-up could work well for a small room or desktop setup. Here's a shot of the Altec Lansing FX5051 set-up, which includes a remote control to manage sound from all six speakers in a 5.1 surround sound rig:
In my view, system builders and consultants will do best offering these USB speakers to clients who seek a PC-based viewing, sound, or gaming station at home or work. To be sure, USB-attached speaker systems offer easy installation and convenient, no-hassle set-up. On the downside, they don't deliver enough sound for use in a large media or family room. For those settings, a USB-attached amplifier with additional speakers will be better suited for the job.
ED TITTEL is a writer and trainer in Austin, Texas, who specializes in Windows topics and tools, especially PC hardware, networking and security.